The major purpose of the proposed study is to better understand the impact of adolescence upon the child's self-image and coping behavior. In 1974 a cohort of 924 children were interviewed in 6th grade and then those who remained in the Milwaukee Public school system were followed from 6th to 7th grade in two different types of school systems: a K-8 system in which children did not change schools in 7th grade and a K through 6 -- Junior High system in which a major environmental change occurred at this time of early adolescence. This cohort was again re-measured as the children made the transition into senior high school in 9th and 10th grade. These surveys explored the impact of pubertal and environmental change upon the child's self-picture and behavior (academic performance and delinquent behavior). The study found that girls experienced the entry into early adolescence as more stressful than did boys. A particularly vulnerable sub-group in terms of disturbance of the self-picture and behavioral reaction were those girls who were undergoing several changes simultaneously: entry into a junior high school, early pubertal maturation, and early experience in "dating" or heterosexual relationships. The negative effects of junior high school remained evident for girls in 9th grade. The question arises whether this disturbance will persist in senior high school and what long-range effects different developmental patterns of puberty and heterosexual relationships will have. Therefore, we propose to continue analyzing the data from this 5 year longitudinal study in order to produce a monograph. Thus, we will be able to investigate whether the children who are at risk in middle adolescence (high school age) are the same as those who demonstrated less favorable reactions to the changes of early adolescence. Secondly, this study will help to set normal baselines against which psychopathology in adolescence can be identified. Finally, such data may aid policy-makers whose concern it is to evaluate different school types, particularly the junior-high school.